A personal diary is biography of a person. Many people write diary and share their experiences with the whole world after they are gone. This is good habbit.
As a kid, I used to write at least 10 sentence on how I spent my day, before retiring to bed. My father made this habit to me. That was to cultivate the writing habit in me. And also I used to draw one picture apart from writing.
I used to write during school and college times. But, now i only write those things whichi want in my life. I have mad one seperate section for " 101 Goal to achieve" and i concentrate on that. I also write about my desires and few quotes which are motivational.
I belive that whatever we write, its effect comes very quickly.
Journal writing is a good habit. I used to do that, but since blog came into the picture, i bet hardly people use pen to write on paper. Everybody is online and writing online diary. However the fun of writing traditional diary is still the same like before. It helps you to think even the spelling of the words, which is an easy job online as software automatically suggest you or correct your spelling mistakes!
I had the habit of writing a diary earlier and it is nice going through them because I get to know what I felt and how life was during those years.However, now I have given up on writing down any of my personal thoughts even on my online blog...never know, I may again start writing a diary since it is a good and useful habit!